Little is known about how participation in community activities influences development and mental health in adolescents and whether individual and interpersonal factors mediate this relationship. The proposed study will address these issues by examining the effects of participation in community activities on depression in a sample of Puerto Rican youth living in Puerto Rico. Data collected will be used to (a) test whether the effects of participation in community activities on depression are mediated by adolescents; perceived social support from peers and mentors and adolescents' sense of self-efficacy, and (b) explore sex differences in depression among adolescents who participate in community activities. The proposed research is relevant to public/mental health objectives in three ways: (1) it employs an integrative approach to the study of developmental processes and mental health issues in ethnic minority adolescents, (2) it identified risk as well as protective factors in the development of psychopathology, and (3) it has the potential to inform the development of intervention and treatment strategies with other ethnic minority adolescents.